package com.leyou.common.utils;
import com.fasterxml.jackson.core.JsonProcessingException;
import com.fasterxml.jackson.core.type.TypeReference;
import com.fasterxml.jackson.databind.ObjectMapper;
import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.io.IOException;
import java.util.List;
import java.util.Map;

/**
 * @author: hehao
 * @create: 2019-03-10 17:20
 **/
public class JsonUtils {

    public static final ObjectMapper mapper = new ObjectMapper();

    private static final Logger logger = LoggerFactory.getLogger(JsonUtils.class);

    public static String toString(Object obj) {
        if (obj == null) {
            return null;
        }
        if (obj.getClass() == String.class) {
            return (String) obj;
        }
        try {
            return mapper.writeValueAsString(obj);
        } catch (JsonProcessingException e) {
            logger.error("json序列化出错：" + obj, e);
            return null;
        }
    }

    public static <T> T toBean(String json, Class<T> tClass) {
        try {
            return mapper.readValue(json, tClass);
        } catch (IOException e) {
            logger.error("json解析出错：" + json, e);
            return null;
        }
    }

    public static <E> List<E> toList(String json, Class<E> eClass) {
        try {
            return mapper.readValue(json, mapper.getTypeFactory().constructCollectionType(List.class, eClass));
        } catch (IOException e) {
            logger.error("json解析出错：" + json, e);
            return null;
        }
    }

    public static <K, V> Map<K, V> toMap(String json, Class<K> kClass, Class<V> vClass) {
        try {
            return mapper.readValue(json, mapper.getTypeFactory().constructMapType(Map.class, kClass, vClass));
        } catch (IOException e) {
            logger.error("json解析出错：" + json, e);
            return null;
        }
    }

    public static <T> T nativeRead(String json, TypeReference<T> type) {
        try {
            return mapper.readValue(json, type);
        } catch (IOException e) {
            logger.error("json解析出错：" + json, e);
            return null;
        }
    }
    @Data
    @NoArgsConstructor
    @AllArgsConstructor
    static  class User {
        String name;
        String age;
    }
   // public static void main(String[] args) {
        User user = new User("jack","21");
        //toString 序列化将对象转换成json数据格式
        //String json = toString(user);
        //System.out.println("JSON="+json);
        //User user1 = toBean(json,User.class);
        //System.out.println("user1="+user1);
        //tolist
        //String json = "[20,-10,5,15]";
        //List<Integer> list = toList(json, Integer.class);
       // System.out.println(json);
       // System.out.println("list="+list);
       //toMap
       // String json ="{\"name\": \"jack\", \"age\": \"21\"\n" +
         //       "}";
        //Map<String, String> map = toMap(json, String.class, String.class);
        //System.out.println("map="+map);

    //}
}
